Code used in "Apex List Comparator | System.ListException: One or more of the items in this list is not Comparable" tutorial on SFDC Stop (https://youtu.be/Sf95Bl_zP2U)

custom-comparator.cls

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Custom Comparator
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List<Integer> numbers = new List<Integer>{ 5, 3, 2, 1, 4 };
System.debug('Initial list of Integers => ' + numbers);

System.debug('Sorting Integers....');
numbers.sort();

System.debug('Final list of Integers =>' + numbers);

System.ListException: One or more of the items in this list is not Comparable.
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class Employee implements Comparable {

    Integer id;
    String name;

    public Employee(Integer id, String name) {
        this.id = id;
        this.name = name;
    }

    public Integer compareTo(Object anotherObject) {
        Employee secondEmployee = (Employee) anotherObject;
        // if( id > secondEmployee.id ) {
        //     return -1;
        // } else if( id < secondEmployee.id ) {
        //     return 1;
        // }
        if( name < secondEmployee.name ) {
            return -1;
        } else if( name > secondEmployee.name ) {
            return 1;
        }
        return 0;
    }

}

List<Employee> employees = new List<Employee>();
employees.add(new Employee(1, 'Richard Hendricks'));
employees.add(new Employee(5, 'Gilfoyle'));
employees.add(new Employee(3, 'Dinesh'));
employees.add(new Employee(2, 'Monica'));
employees.add(new Employee(4, 'Erlich Bachman'));

System.debug('Initial List: ');
System.debug(employees);

System.debug('Sorting Employees....');
employees.sort();

System.debug('Sorted List: ');
System.debug(employees);